Electron mobility AlGaN

Li, Y. Xiang, J. Qian, F. Gradecak, S. Wu, Y. Yan, H. Blom, D. A. Lieber, C. M. 2006. Dopant-free GaN/AlN/AlGaN radial nanowire heterostructures as high electron mobility transistors. Nano Lett. 6 1468-1473. 

Two types of high electron mobility transistors (HEMTs) with 2D electron gas were made from AlGaN/GaN heterostructures grown by MOCVD on Si (111) substrates, and their electrical DC properties were compared. Optical study, namely photoluminescence, photoreflection and reflection spectroscopy of the structures was performed. The strain values in GaN layers (6.6 and 1.7 kBar) and electric field strength near the heterointerface (470 and 270kV/cm) were determined. A correlation between the HEMTs DC characteristics and the optical properties of GaN layers was demonstrated. 

Kang, B., Pearton, S., Chen, X, Ren, E, Johnson, J.,Therrien, R., Rajagopal, P, Roberts, X, Finer, E. and Linthicum, K. (2006) Electrical detection of deoxyribonucleic acid hybridization with AlGaN/GaN high electron mobility transistors , App//ed Physics Letters, 89(12). 

Kang, B., Ren, E, Wang, L., Lofton, C., Tan, W., Pearton, S., Dabiran, A., Osinsky, A. and Chow, P. (2005e) Electrical detection of unmobilized proteins with imgated AlGaN/GaN high-electron-mobility transistors AppZ/ed Physics Letters, 87(2). 

Neuberger, R., Muller, G., Ambacher, O. and Stutzmann, M. (2001) High-electron-mobility AlGaN/GaN transistors (HEMTs) for fluid monitoring applications , Physica Status Solidi a-Applied Research, 185(1), 85-89. 

Zhang, A. E, Rowland, L. B., Kaminsky, E. B., Tilak, V., Grande, X C., Teetsov, X, Vertiatchikh, A. and Eastman, L. F. (2003b) Correlation of device performance and defects in AlGaN/GaN high-electron mobility transistors . Journal of Electronic Materials, 32(5), 388-394. 

Figure 5.17 Electron mobility at room temperature of n-type Si-doped a-plane GaN grown on r-plane sapphire. Planar GaN grown on AlGaN/AiN intermediate layer is indicated by Template (circles). SELO indicates GaN grown with the SELO process (squares). That of c-plane GaN grown on sapphire using a low-temperature buffer layer is also shown for comparison (cf Color Plate XXVI).

To apply nonpolar nitrides to devices such as high-electron-mobility transistors and UV emitters/detectors, AlGaN is an essential material. However, when AlGaN is grown on GaN, cracks are generated by tensile stress when the layer... 

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